Automatic switch



Patented June 7, 1927.

mrs

CLIN'ioN n. sIrE, or CHICAGO, ILLINOIS, lau'ronrarrc ELECTRIC INC., or CHICA WARE.

ASSIGNOR, BY MESNE ASSIGNMENTS, T G0, ILLINOIS, A CORPORATIQN 0F DELA- .AUTOIVIATIC SWITCH.

Application led September 11, 1922, Serial No. 587,502. Renewed October 30, 1926.

This invention relates in general to automatic switches for telephone systems, and may be considered as being an improvement on Patent 1.603.929, issued Oct. 19, 1926, to

John Wicks. The object ofthe invention is the provision of a new and improved rotary connector switch.

More specifically, oneI pbject of the invention is to provide a rotary connector switch having both directive and automatic pri mary or vertical movements, and having both directive and automatic secondary 0r rotary movements, and having' means for preventing lthe directive secondary Inovement oi the switch after the switch has taken an automatic primary step. Y

The provision of a connector having the foregoing characteristics makes it possible to form large groups of trunks by combining two or more levels, or by combining one or more levels with any desired portion of an adjacent level, while at the same time another levcl may be divided in several smaller groups.

The means by which the foregoing and other objects are accomplished will be fully set forth hereinafter, reference bein had to the accompanying drawings7 of which Fig.

l is a. circuit diagram of the improved connector, while Fig. 2 shows the wiring of the test terminals in certain levels of the connector bank.

Referring to Fig. 1, the rotary connector is and may be of the well-known Strowger vertical and rotary type, having circuits such that it is controlled over the two sides of the incoming trunk in series. To the right ot' the connector H are shown the bank ter- 4o minals of a trunk line, which may extend to a private branch exchange and termina-te in a jack. lt is understood that the trunk line shown is one of' a group of trunk lines all extending to the same point.

ln Fig. 2. the test terminals in the first five levels of the connector have been shown. The testy terminals are so connected that the five levels comprise two large groups, two small groups, and three individual lines. The rst large group consists of three subgroups, the rst sub-grorp consisting of the trunk terminals in the ,rst level, the secl indicated by the reference character H,

ond sub-group consisting of the trunk terminals in the second level, and the third sub,- group consisting of the first five trunk terminals in the third level. The second large group consists of two sub-groups, the first sub-group consisting of the last five trunk terminals in the third level, and the second sub-group consisting of the trunk terminals in the fourth level. The first and second sub-groups in the first large group and the first sub-group in the second large group as shown, are equipped with chain relays, which are connected to the bottom test terminals of their res Jective trunk lines. To the right of the ban terminals are shown the vertical test terminals, two for each level. When a.. trunk line is seized, the chain relay associated therewith energizes and completes at its working contact a portion of a circuit for placing a guarding potential on one of the vertical test terminals opposite the level in which the trunk line is located. When all the trunk lines in the first and second subgroups of the first large group are busy, all of the chain relays 'associated therewith will be'energized, and circuits will be co1nplete-d through the working contacts of the chain relays for 'placing guarding potentials on the vert-ical test termlnals opposite such sub-groupsk The first sub-group in the second large group places a guarding potential on one of its associated vertical test terminals in a similar manner. It will be noted that the last sub-group in each large group vand the smaller -groups have no means for placing a guarding potential tive Vertical test terminals, as none is needed. Thosetest contacts which are not provided with chain relays are, howeverq connected to battery through aresistance. except in the case of straight or ordinary subscribers lines, the test contacts to battery through the cutI oft` relays in the usual manner. The vertical test wipers are arranged to wipe over the vertical test terminals in the vertical movement, and to disengage therefrom on the rotary movement.

On the drawing, relays which have slow on their respec` acting characteristics are denoted by thel` shading on the lower ends of their cores, or

else by the solid black portion on the upper ends of their cores. The relays which have of which are connected cores shaded on the lower end are the usual so-called slow acting relays and are slowv to fall back but not noticeably slow to pull up. On the otherhand, the relays which have the upper ends of their cores shown solid black are slightly slow to pull up, in addition to being slow to fall back.

vThe apparatus .having been described more or less in general, will now be described in connection with a detailed description of its operation. For this purpose, it will be assumed that an automatic subscriber desires to obtain connection with a subscriber in the private branch exchange served by the first large group of trunk lines. The customary subscribers substation, and selector switches used by an automatic subscriber in completing a connection being well understood by those skilled in the art and forming no part of the present invention, it is believed that it will suffice to say that in response to the removal of the receiver by the calling subscriber, his individual line switch seizes an idle trunk line leading to an idle selector switch; and in response to the operation of the subscribers calling device, the selector switch is operated to select an idle trunk line leading to another idle selector switch, or to select an idle trunk line leading to a connector switch,

` such as indicated by the reference character H. Let us assume that the calling subl scriber has established his connection up as far as the last selector, and that the selector has come to rest on its bank contacts which are connected to the conductors 20, 21, and 22 of the connector switch H, the connector switch H being the first idle connector accessible to said selector. VVheli the selector switch comes to rest upon the contacts associated with conductors 20, 21, and 22, the switching relay of the selector completes an energizing circuit for the line relay 4 of the connector switch as follows: from ground by way of lower winding of line relay 4, normally closed springs controlled by the armature 31, conductor 21, over the intervening switches and the subscrbers loop back to conductor 20, normally closed springs controlled by the armature 30, and through the upper winding of line relay 4 to battery. Relay ll, at armature 32 and its working contact, completes an energizing circuit for slow`to release relay 5. Relay 5, upon energizing over the above traced circuit, connects ground to the release conductor 22 at armature 33 and its working contact, said ground completin a holding circuit for the switches back of t e connector switch for maintaining said switches in an operated position, and, in addition, making the trunk line leading to the connector H busy to all other selectors having access thereto. At armature 34 and its working contact relay 5 prepares a circuit for the vertical magnet 15,

individual line switch,

and at the resting contactof the same armature opens a point in the release-circuit.

The calling subscriber may now manipulate his calling device in accordance with the remaining digits in the number of the private branch exchange, which in this case are 1 and 1. Due to the operation of the calling device by the calling subscriber, the circuit of the line relay 4 is interrupted in a well-known manner and the line relay, in response to this circuit interruption, deenergizes for a short interval and closes a circuit for the vertical magnet 15 as follows: from ground by the way of armature 32 and its resting contact, armature 34 and its working contact, normally closed o normal spring controlled by spring 68 and s'aid spring, slow acting relay 6, and vertical magnet 15 to battery. The vertical magnet 15 and relay 6 energize in series, and by the operation of the vertical magnet 15, the switch shaft and wipers are raised until the Wipers -78, inclusive, are opposite the first level and the verticaltest wipers 90 and 91 are in engagement with vertical test terminals 92 and 93, respectively, which are opposite the first level. Relay 6 energizes and at armature 35 and its working contact maintains ,its own circuit and that of the vertical magnet 15 intact after the off normal springs have shifted, which they do on the first vertical step yat armature 36 and its resting contact opens the rotary circuit, at armature 37 and its working contact prepares a circuit for relay 9, and at armature 38 opens the vertical testing circuit.

After the first impulse, the line relay 4 again energizes and opens the circuit for relay 6 and vertical magnet 15 at armature 32. Relay 6, upon deenergizing, which it docs after a short interval, switches the impulsing circuit from the vertical magnet to the rotary magnet at armature 35, and at armature 38 completes a testing circuit for vertical wiper relay 8 and vertical stepping relay 7.

If all the trunk lines in the first level arc busy, there will be a ground potential on the vertical test terminal92 caused bythc energization of the chain relays shown just below the first level (Fig. 2). Each chain relay, upon energizing whenits associated trunk lineis seized. completes its 'portion of a chain of contacts by means of which ground is connectedvto the vertical `test terminal. J

Assuming that all the trunk 'lines in the first level are busy, the 'relay 6, upon deenergizing, completes an energizing circuit for the vertical wiper relay 8 as follows: from ground by'the way of chain relayfcontacts, vertical test terminal 92, vertical wiper 90. resting contactv of armature 38 and said armature, normally closed springs controlled by the armature 45, normally closed springs,

controlled by armature 42, and relay 8 to battery. Relay 8, upon energizing, completes alocking circuit for itself as follows: from gi'ounded release conductor 22, -by way of armature 42 and its working contact., and relay 8 to battery. At armature 43 and its resting contact relay 8 opens the rotary inipulsing circuit so that anyfurther operation of the calling device by the calling subscriber is prevented from operating the'rotary magnet, at armature 44 and its Working contact prepares a circuit for relay 9; unil at armature 45 and its working contact switches the vertical testing circuit from vertical test. wiper 9() to vertical test wiper 91. Relay 7 energizesat. the. same time. relay 8 energizes as follows: from grounded vertical" test wiper 9() over a portion of tbe above traced circuit to armature 70 and its resting contact, and relay 7 to battery. Relay 7. upon energizing, completes a locking circuit for itself as follows: from grounded rel-ease conductor 22, working contact of armature 4() and said arinatui'e, ai'niatiire Tt) and its resting contact, and relay 7 to battery. At armature 39 and its working contact relay 7 completes an energizing circuit for relay 6 and vertical magnet 15 as follows: from grounded release conductor 22, working contact of armature 39 and said armature, relay 6, and vertical magnet 15 to battery. Relay 6, upon energizing, completes an energizing circuit for thev rotary stepping relay 9 which energizes; and at armature 86 opens the circuit of the i'otary magnet 16. The vertical magnet 1f'. upon energizing, raises the switch` shaft and wipers opposite the nextor second level and the vertical test Wipers 90 and 91 come into engagement with the vertical test terminals 94 and 95, respectively. The vertical magnet 15, at its interruptor springs 70, opens the locking circuit for relay 7, whereupon said relay deenergizes and opens the circuit for relav 6 and the vertical magnet 15 at armature 89. The relay 6, dueto its construction, is slow to rel-ease `and maintains its armatures attracted a. short interval after its circuit is broken. The vertical magnet 15, however, immediately deenergizes and completes a testing circuit for vertical stepping relay 7 by way of armatures 70 and 45 and vertical test wiper 91. The slow acting relay 6 then deenergizes, providedthere is no ground potential on vertical test terminal I 95. If. however, all the trunk lines in -tlie second level are busy. therewill be a ground potential on vertical test contact 95 and relay 7 will again energize as follows: from ground by the way ofthercontacts of the chain relays in the'second level, vertical test terminal 95, vertical test wiper 91, armature 45 and its working contact, interrupter springs 70, and relay 7 to battery.

`Relay 7, upon energizing, again completes a locking circuit vl'or itself at'variuature 40 as previously explained; and at armature 39 reestablishes the circuit for relay 6 und v crtieal magnet 15. The relay 6, being slow acting, has inaintaincdx its armatures at-i tracted during tlie interv ll so that the rotary magnet 16 is not operated.4 The vertical -magnet 15 operates again now, opens the locking circuit of relay 7, and steps the swtch shaft and wipers up to the next or third level.v

On the deenergization of thee vertical 1nagne't,vertical test wiper 91 again tests for a ground potential, and this` se (pience of operations continues until the vertical test wiper 91 no longer finds a ground potential, or until it comes into engagement with a dead contact, whereupon the relay deenergizes, as no circuit is established for the vertical stepping relay 7 and tti-z` vertical trunk hunting will stop.

Returning now to just after the first automatic vertical step, and assuming that only the first three trunk lines in the second level are busy, the vertical stepping relay 7 will not again energize due to there being no ground potential on the vertical test terminal 95. The rotary stepping relay 9, upon energizing, as previously explained, establishes a locking circuit for itself as follows: from grounded release conductor 22 by the way of working contact of armature 46 and said armature, interruptor springs 71 of the rotary magnet 16, and relay 9 to battery. Relay 9 is maintained energized during' the automatic vertical trunk hunting movement lor) and performs nor functions until the slow acting relay 6 fully deenergizes. Slow acting relay 6, upon deenergizing, opens the loriginal energizing circuit for relay 9 at armature 37; and at armature'BG audits resting contact completes an energizing circuit for relay 13 and the rotary magnet 16 as follows: from ground by the way of grounded release conductor 22, working contact of armature 47 and said armature, armature 36 and its resting contact to junction point 99, where the circuit divides, one branch going by way of armature 66 and its resting contact, and winding of rotary magnet 16 to battery, the other branch going by Way of resting contact of armature 52 and winding of relay 13 to battery. Relay 13, upon energizing, prepares at armature 58 a circuit for the rotary stepping relay 9; at armature 59 and at its working contact prepares a circuit for the testing relay 12; and at armature 69 disconnects the busy machine. The rotary magnet, upon energizing kover the above .traced circuit, rotates the wipers 75-78, in-

clusive, into engagement with the first set of bank contacts in the second level, and moves the vertical test wipers 90 and 91 out of engagement with the vertical test contacts 94 and 95, respectively. In addition, the rotary magnet opens the locking circuit level to be busy, there will be a ground potential on the test terminal which the test wiper 77 cornes into engagement with, said 'ground extending from the connector switch occupying a multiple of that particular trunk line from a ground connection and armature similar to ground and armature 64 of the'connector switch H. If the first trunk line in the second level is busy, ground from the lower private bank terminal of said trunk line energizes test relay 12 by way of test wiper 77, normally closed springs controlled by the armature 64, armature 59 and its working contact, armature 65 and its resting contact, windingbf test relay 12 to battery. -Relay 12, upon energizing, at armature 57 prepares a circuit for the trans mitting of a busy tone to the calling subscriber; at armature and its working contat prepares a locking circuit for itself; and at armature 54 and its working contact closes an energizing circuit for the rotary stepping relay 9 as follows: from ground potential on the bottom test terminal, over the short conductor connecting the upper 1 and lower test terminals and from thence by way of test wiper 76, armature 58 and its working contact, working contact 4of armature 54 and saidarmature, resting contact of armature 51 and said armature, interrupter springs 71 of the rotary magnet, and winding of relay 9 to. battery. Relay 9, upon energizing, completes a locking circuit for itself, and, in addition, again completes energizing circuits for relay 13 and the rotary magnet 16 as previously described. It is to be noted that relay 13, being a slow to release relay, has not had time to fully deenergize before the rotary stepping relay 9 was energized, with the result that the slow to release relay is maintained energized during the automatic rotary movement. The rotary magnet 16, upon energizing, steps the wipers 7 578, inclusive, into engagement with the next or second set of bank terminals in the second level, and at its interrupter springs 71 opens the locking circuit for the rotary steppmg relay 9, whereupon said relay deenerglzes. Relay 9, upon deener gizing,l again opens a point in its own lockmg circuit and 'again opens the circuit of the rotary magnet 16 and the slow to release relay 13. The rotary magnet on deenergizing, at its interrupter springs 71 again prepares the circuit for relay 9, and the testing operation continues in the described manner until an idle set of contacts is reached.

Assuming the fourth trunk line in the second level to be the iirst idle trunk line, the test wipers 76 and 77 Will come to rest in engagement with the test terminals and 81, respectively. As the. test relay 12 no longer finds a ground potential on the test terminal 81 with which it is now in engage ment,'said relay deenergizes and prepares a circuit for the switching relay 14 at armature 55; at armature 54 opens the circuit for the stepping relay 9, and at armature 57 opens the busy circuit. A short interval at'ter relay 9 deenergizes, the slow acting relay `13 deenergizes and completes a circuit for the switching rela 14 as follows: form grounded release con uctor 22 by the way of armature 55 and its resting contact, lower winding of switching relay 14, resting contact of armature 59 and said armature, normally closed springs controlled by the armature 64, wiper 77, test terminal 81, conductor 73, and Winding of chain relay 18 to battery. The switching relay 14 and the chain relay 18 energize in series. The chain relay 18, upon energizing, closes its springs 74, thereby completing one of a chain of contacts for grounding the vertical test contact 95. The switching relay 14, upon energizing, closes at armature 62 a circuit through the low capacity condenser 98, whereby the calling subscriber is given the well known ring back tone when ringing current is applied to the called line; at armature 66 permanently opens the circuit for the rotary magnet; at armature 64 grounds test wiper 77; at armature 65 opens the circuit for the testing relay 12, at armature 63 completes a locking circuit .for itself from vgrounded release conductor 22, and at armatures 61 and 67 connects ringing current to the trunk line, which current operates a visual si nal at the operators position in the private ranch exchange. The circuit for ringing the visual signal or drop at the private branch exchange may be traced as follows: by the operation of the interrupter relay 17, groundedgenerator and booster battery are alternately placed on armature 72, and from thence the circuit may be traced through the upper winding of the ring cut olf relay 10, resting Contact of armature 48 and said armature, armature 61 and its working contact, wiper 75, line bank terminal 79, through the jack, condenser and drop (not shown) at the branch exchange back to line bank terminal'82, wiper 78, working contact of armature 67 and said armature, and armature 5() and its resting contact to ground. The ring cut oft' relay 10, due to its construction, the condenser and the high v. y resistance ofthe drop in the branch exchange will not energize over the above traced circuit; the drop, however,is o erated'over the above traced circuit to disp a to the operator at the private branch exc ange a visual signal by means of which the operator is informed that a connection is desired. The operator, in response to the. signal, inserts the answering plug of one of her cord circuits into the `Jack at the branch exchange, thereby disconnecting the drop and completing a circuit for the ring cut oi relay 10 by closing a relatively low resistance bridge across the trunk. Ring cut oi relay 10, upon energizing, completes a locking circuit for itself at armature 49 from grounded release conductor 22; and at armatures 48 and 50 disconnects ringing current from the called line and completes the talkin circuit between the calling subscriber and t e operator. The back bridge relay 3 is now energized over the trunk and reverses the How of current to the calling subscriber at armatures 30 and 3l. The-operator, upon ascertaining the wants 'of the calling subscriber, completes the desired connection and conversation is 4carried on in the usual manner.

After conversation is finished both parties replace their receivers. When the calling subscriber hangs up he opensthe circuit of the line relay 4, whereupon said relay deenergizes and opens the circuit of relay 5. After a short interval, relay 5 deenergizes and removes ground from the release conduct-or 22, thereby allowing all the switches back of the connector H to release and restore to normal. In addition, atarmature 33, relay 5 opens the locking circuits for relays 10 and 14, allowing said relays to release, and at armature 34 completes a circuit for the release magnet 19 to allow the switch H to return to normal. The release magnet 19 is energized over the following path: from ground at armature 32 and its resting contact, armature 34 and its resting contact, ofi' normal spring 69 and its working contact,

and release magnet 19 to battery. The release magnet is maintained energized over the above traced circuit until the shaft and Wipers are returned to their normal position, whereupon the circuit of the release magnet is opened by the separation of the ofl:l normal springs.

Having described the operation of the switch in connection with establishing a connection with a private branch exchange, a. brief description will now be given how the calling subscriber receives the busy signal when all t-lie trunks to the private branch exchange are busy.

When the first digit is transmitted to the connector, the vertical magnet is operated to step the shaft and wipers up to the first level, as previously explained. With all the trunk lines busy,there will be a ground potential on the vertical 95 and tlie'vertical magnet will automatical- 1y operate as previously explained, to step the shaft and wipers up to the third level. In response to the deenergization of relay 6, the rotary movement of the switch is started. The first five trunk lines Vin the third level boing busy, the Wipers are automatically rotated into -engagement with the fifth set` of bank contacts in the third level. As will be noted in Fig.`\2, the two test terminals 23 and 245 are not strapped together and the switch will stop with its wipers 76 and 77 1n engagement with said test terminals, as a circuit is no longer completed' for the rotary stepping relay 9. Ground, however, on test terminal 24 maintaiis the testin relay 12 energized and said relay is locke up from the grounded release conductor 22 when relay 13 deenergizes. When relay 13 is fully deenergized, the busy tone is transmitted to the calling subscriberthrough armatures 60 and 57 in the well known manner, whereupon the calling subscriber hangs upand releases the switch as previously .described.

It will also be noted that the last pair of test terminals in the first and second levels are not strapped although ordinarily .all pairs 1 n a group are strapped except vthe last pair. The reason for this is that should there be but one idle trunk in one of the levels, say the second level, and two connector switches such as H should start rotating nearly simultaneously to seize said idle trunk line, one of the connector switches would reach the idle trunk line before the other and make-it busy to said other connector switch. The other connector switch would continue to rotate until it reached the last test terminal in the second level, where it would stop and transmit to the calling subscriber a busy signal as previously described. j

It will now be assumed that an automatic subscriber desires to obtain connection with a subscriber in the private'branch exchange served by the second large group of trunk lines and that he has established his connection up to and including the connector switch H. p The calling subscriber may now manipulate his calling device in accordance with the remaining digits in the number of the branch exchange, which in this case are3 and 6. In response to the operation of the calling device by the calling subscriber the shaft and wipers of the connector switch H are raised opposite the third level in the same manner as previously described.

Assuming that there is at least one idle trunk line in the second half ofthe third level, there will be no ground potential on Athe vertical test terminal 96 which is now engaged by the vertical test wiper 90, and the test 'Contacts 92 and4 relay 6, upon deenergizing as previously explained, prepares the rotary 1m ulsmg circuit without completing circuits o r the verticlal stepping relay 7 and the vertlcal Wiper re ay 8.

The subscriber may now dial the remaining 'or last digit of the called number, or the digit 6. In response tothe operation of the calling device by the calling subscriber, p

the circuit of the line relay 4 is again intermittently interrupted. Each time the line relay deenergizes, it completes a circuit for the rotary magnet 16 in series with relay 1-1 as follows: from ground by the way of armature 32 and its resting contact, armature 3l and its working contact, normall open olf-normal springs controlled by sprlng 68, armature 35 and its resting contact, armature 43 and its resting contact, armature 56 and its resting contact, winding of relay 11, armature 66 and its resting contact, `and winding of rotary magnet 16 to battery. The rotary magnet 16 and-relay 11 energize in series. The rotary magnet 16 steps thev Wipers 'f5-78, inclusive, into engagement with the bank terminals of the Sixth trunk in the third level, and moves the vertical test wipers and 91 out'of engagement withv vertical test contacts on its first rotary step. Relay 11, upon energizing, at armature 53 and its working contact maintains the impulsing circuit for the rotary magnet closed, so that said impulsing circuit Will not be opened at armature 56 when the Wipers are passing over busy trunks, at armature 51 and its resting contact opens the circuit to relay 9, so thatsaid relay will not energize when Wiper 76 is passing over busy trunks, and at armature 52 and its working contact, completes an energizing circuit for relay 13,/ Relay 13, upon energizing, at armature 58 and its working contact prepares a circuit for relay 9; at armature 60 disconnects the busy machine; and at armature 59 and its working contact prepares the testing circuit for relay 12. The operation of the switch now depends on Whether the trunk line with which the wipers are in engagement is busy or idle, and the operation in either case will be the same as previously described, that is, if the sixth trunk is idle itwill be connected with, whereas if this trunk is busy the switch will rotate automatically under control of relay 9 until an idle trunk is found.

A briefy explanation will'noW be given how `a subscriber calls the private branch exchange served by the second large group of trunks. when all the trunks in the first subgroup of such group are busy. In response to the operation of the calling device by the calling. subscriber the connecter switch H is directively operated to raise its shaft and wipers opposite the third level, and is then automatically operated to raise its Wipers opposite the, fourth level, afterwhich the automatic rotary movement is initiated. The subscriber may now dial the last digit of the called number or digit 6. In response to the operation of the calling device by the calling subscriber, the circuit of the line relay is again intermittently interrupted, but due to the opening of the rotary imulsing circuit by wiper relay 8 atarmature 43, the operation of the line relay performs no function other than to vibrate its armature in response to the interruptions in the line circuit. If the rotaryimpulsing circuit was not opened at armature 45 during the first automatic vertical step, "the subscrib- 80 ers impulses caused by the dialing'of the digit 6 would be effective to rotate the wipers past the first five trunks and into engagement with` the sixth set of bank contacts in the fourth leiiel. It is, therefore, plainly seen that the first five trunks in the fourth level would always be inaccessible unless some provision was made for preventing the secondary directive or rotary movement after the switch has taken an automatic vertical step. With the Wipers-in engagement with the first trunkfline vin the fourth level the trunk line is tested and if found busy the switch automatically rotates the Wipers insearch of an idle trunk in the same manner as previously described.

A brief explanation will now be given how the connector switch establishes connection with a trunk in a small group, such as the group shown in Fig. 2, comprsin the me sixth, seventh, eighth, and ninth set of ank contacts in the fifth level. The digits necessary to call this group are the digits 5 and 6, and in response to the subscriber dialing the first digit or digit 5, the switch raises its shaft and Wipers opposite the fifth level.

The subscriber may now dial the remaining or last digit of the called number or the digit 6. In response to the operation of the calling device by the calling subscriber, the wipers of the switch are rotated into engagementwith the sixth trunk line in the fifth level. If this trunk line is `busy the wipers are rotated in search of an id'le line and if none is found the Wipers will stop on the ninth trunk line in the fifth level and transmit the busy signal to the calling subscriber in a well known manner.

The connector switch is also capable of completing connection with a private or in- 12udividual line, the test terminals of three of such individual lines being shown as the fourth, fifth, and tenth sets of contacts in the fifth level in Fig. 2. Connections to these lines, however, are directively controlled throughout by thel calling subscriber. I The desired line is not tested until the wipers have been rotated into engagement with the bank terminals of the desired line, whereupon the desired connection is com- 13o leted if the line is idle, or if4 the line is usy, the busy toneis given the calling subscriber in the well known manner.

Having fully described and ascertamed the features of my invention whatis considered to be ne and desire r to have protected by Letters atent 'will be pointed out 'in the ap ended claims.

What claim is:

.1. In a telephone system, a rotary connector, lines divided into groups and subgroups accessible to said connector, means for directively controlling the operation of said connector` in a primary movement to select a group, means for contmumg the primary movement to automatically select a sub-group in said group, dlrectively controlled means for operatlng sald connector in a secondary movement, means for. preventing theoperation of said last mentioned directively controlled means, means for automatically starting the secondary movement. and means for automatically continuing the secondary movement to select an idle line in said sub-group.,

In a telephone system, a connector switch having a directive and an automatic primary movement Aand a directive and an automaticfsecondary movement, means for directively and automatically operating said switch in its primary movement, means for preventing the directive operation of said switch in its secondary movement, and means forv automatically operating said switch in its secondary movement.

3. In a telephone system, a rotary connector, lines divided into groups and subgroups accessible to said connector, a primary motor magnet for operating said connector in a primary movement to select a group in accordance with a. digit of the called number. means for continuing the primary movement to automatically select a subgroup in the selected group, a secondary motor magnet for operating said connector in a secondary vmovement in accordance 'with another digit of the called number, means responsive to the lautomatic primary movement for preventing the directive operation ofv said secondary motor magnet, and means for automatically operating said secondary motor magnet to select an idle line in the selected sub-group.

4. In a telephone system, a `connector switch having :r primary motor magnet directively and automatically controlled to operate said switch in a primary movement and a secondary motor magnet directively and automatically controlled. to operate said switch in a secondary movement, means for directively and automatically operating said primary motor magnet to move said switch in its primary movement, means for preventing the direct-ively controlled operation of said secondary motor magnet, and means for automatically operating said secondary motor magnet to move said switch in its secondary movement.

5. 1n a telephone system, a rotary connector, lines dlvided into groups accessible to said connector, said groups divided into sub-groups, means for directively controlling the operation of said connector in a primary movement to select the first sub-group in the selected group, means controlled by the busy condition of the lines in said first sub-group for continuing the primary movement to` automatically select another sub-group in said group, directively controlled means for operating said` connector in a secondary movement, means controlled in response to said continuation of said primary movement for preventing the operation of said last mentioned directively controlled means, and means for automatically operating said connector in its secondary movement to select an idle line in said other sub-group.

6. In a telephone system, a connector switch having directive and automatic primary movements and directive and automatic secondary movements, trunk lines accessible to sai switch arranged in groups and sub-groups, means Yfor directively operating said switch to select the first sub-group in a desired group, busy condition of the selected sub-group for automatically operating said switch in its primary movement to select an idle subgroup, and means effective whenever said switch is operated automatically in its primary movement for preventing directive control of its secondary movement.

7. In a telephone system, a connector switch having directive and automatic primary movements and directive and automatic secondary` movements. trunk lines accessible to said switch arranged in groups and sub-groups, means for dircctively operating said switch to select the first sub-group in a desired group, means contingent on the busy condition of the selected sub-group t'or automatically operating said switch in its primary movement toV select an idle suhgroup, means effective whenever said switch is operated automatically in its primary movement for preventing directive controll of its secondary movement, and means operated automatically on the completion of the automatic primary movement for initiating the automatic secondary movement.

8. The combination, with an automatic hunting switch, of two test Wipers for con? trolling the same hunting operation, the irst of said wipers being normally connected for use, and means effective during the hunting operation forsubstituting the second wiper for the first.

9. The combination, with an automatic switch having automatic group and line selecting movements, of two group test wi pmeans contingent on the y ers and two line test wipers for controlling said selecting movements, and means etlective during the group selecting movement for substituting one group test wiper for the other.

10. The combination, with a three-motion automatic switch having a directive primary movement and an automatic hunting movement in the same direction, of a test wiper brought into use at the end of the directive primary movement to start the hunting movement, and a sccondtest wiper for determining the extent of the hunting movement.

11. The combination, with an automatic directive switch, ot means for giving said switch an automatic huntng movement in addition to its directive movement, a test wiper for determining whether or not said hunting` movement takes place, a second test wiper for determining the extent of the hunting movement, and means responsive whenever the hunting movement is initiated for disconnecting thel first of said wipers and for connecting the second.

12. The combination, with an autonxatic hunting switch, of two test wipers for controlling the hunting operation, the first of said wipers being normally connected to start the hunting movement, and means effective whenever the `hunting movement starts for substituting the second wiper for the first.

13. The combination, with anautomatic hunting switch, ot two test wipers for controlling the hunting operation,'the first of said wipers being normally connected to start the hunting movement, and means responsive whenever the hunting movement is initiated for substituting the second wiper l'or the first.

14. In a telephone system, a connector switch having directive group and line selectinof movements, and means effective in case .Il the lines in a selected group are busy for preventing the operation of the switch in its directive secondary movement.

15. In a. telephone system, a connector switch having two directive movements, groups of contacts adapted to be selected in the lfirst of' said movements, two motor magnets and circuits therefor, and means effective in case the operation of the first motor magnet positions the switch opposite a busy group for opening the circuit of the second motor magnet.

16. In a rotary connector, bank contacts arranged in levels, a group of trunk lines terminating in the contacts of a` certain level and in a portion of the contacts ot another level, and a second group of' trunks terminating in the remaining` contacts of said other level and in the contacts of a third level.

17. In a rotary connector, two groups of trunklines, two groups of bank contacts in said connector assigned to said groups of trunk lines, respectively, and a third group of bank contacts in said connector divided between said groups of trunk lines.l

18. The combination of a switch having two directive movements, of' means effect-ive under predetermined conditions for giving the switch an automatic hunting movement :following the Vfirst directive movement, and aneans responsive to said hunting movement for preventing the second directive movement.

19. The combination, with an automatic switch having two directive,niovements, of groups of trunk terminals adaptedy to be selected by the first directive movement, and means for preventing the second directive movement in case the group selected on the first movement is busy.

20. The combination, with an automatic switch having two directive movements and' two hunting movements, of groups of trunk terminals any one of which groups may be selected on the first directive movement, means dependent on the idle condition of the selected group of terminals for cancelling one hunting movement, and means operable.

responsive to the busy condition of the selected group of terminals for preventing the second directive movement.

21. In a telephone system, a first and a second motor magnet, means for directively generating impulses to successively operate said magnets, means for automatically generating impulses to automatically operate said magnets, and means responsive to the automatic operation of said first magnet for preventing the directively generated impulses from operating said second magnet.;

22. In a telephone system, a first and a second motor magnet, means for directively generating impulses to successively operate said magnets, means operated under predetermined conditions for preventing the operation of said 'second magnet by said impulses, means for automatically generating impulses, and means operable under said predetermined conditions for operating first the first magnet and then the second magnet by said automatically generated impulses.

23. In an automatic switch having both directive and automatic primary and secondary movcments, means for automatically starting the automatic primary movement of said switch, and means effective responsive to said automatic primary movement for preventing the operation of said switch and its directive secondary movement.

24. In an automatic switch, means for directively controlling the movement ofsaid switch in one direction, means for directively controlling the movement .ofI said switch in another direction, means for automatically continuing the. movement of the switch in the first direction, and means responsive to said last means for preventing the operation of said switch in its second directive movement.

25. In a telephone system, a group of lines terminating in a plurality of groups of line bank contacts, roups of test conta-cts associated With sai line bank contacts, a first and a second auxiliary contact associated With each group of test contacts, means for placing a guarding potential on the first of said auxiliary contacts associated with the first group of bank contacts when all the contacts in the first group are busy, means for placin a guarding potential on the second of sai auxiliary contacts associated with the second group of contacts when all the contacts in the second group are busy, an automatic switch having access to said groups, and means controlled by the guarding potential on said first and second auxiliary contacts for causing said switch to move to a third group of bank contacts.

` 26. The combination, with an automatic `switch having directive and automatic group selecting movements, of two group test wipers, and means for testing with both Wipers to control the automatic group selecting movement.

In Witness whereof, I hereunto subscribe my name this 29th day of August, A. D., 1922.

CLINTON R. SIPE. 

